Musings on Science

Temporal Cloaking

This experiment is a little too fantastic for me not to keep coming back to it. I’m referring to the experiment conducted by Cornell physicists, who played around with a couple of fundamental qualities of light to make something that I’m inclined to call magic.

That sentence doesn’t really do justice to the ingenuity of the experiment, so here’s a link to a lovely animation by the folks at SciAm.

Obviously light travels, in a vacuum, at the same blistering speed of about 300,000,000 m/s, but in specific media, blue light for instance travels faster than red light. In other media, the effect is reversed. And that’s the — if not simple, then fairly well-known — law of light that the researchers have used to create this experiment.

The Limitations

This doesn’t, of course, mean that we’re going to see secret underground societies of the future secretly traveling by temporal cloaking or anything. The effect was created for all of 50 picoseconds. That’s an impossibly small amount of time — each picosecond is a trillionth of a second, a zero followed by a decimal point and 11 friends, before the 1. The internet seems to agree that a blink lasts about 300 to 400 milliseconds. The experiment would have to create 6 billion such precisely timed blips in time for someone to vanish for the blink of an eye.

There’s also the problem of the technology not exactly being, well, cloak-like. The experiment involves lasers and a lot of optical fibre, according to the Cornell Chronicle’s story, and while that’s relatively low tech, it’s not about to be, say, the Dark Knight’s latest gadget.

The Possibilities

The story linked above, to Cornell’s site, actually posits a couple of use cases for the technology that I didn’t see many papers mentioning. Author Steele talks about inserting emergency signals and multitasking operations on a photonic computer, which are very exciting in and of themselves.

What’s interesting is that we don’t have to look too far into the future to see a potential for science fiction here. Most computers or laptops these days perform at close to 3 GHz, which means that every calculation takes 333 picoseconds. If the research can ratchet up the temporal blip to something close to that number, you could lose one cycle of calculation in a run-of-the-mill computer; in a supercomputer, more could be lost.

I can imagine something pretty destructive happening if this technology went underground. It may not take much to disrupt the sending of one packet of data; that could scramble sensitive communications.

It’s still a little further into the future, but quite fun to think of.